Improvement in steam-engines



NITED STATES PATENT rrlcn.

NATHAN ATHERTON, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN STEAM-ENGINES.

Specification forming part of Letters Patent No. [1,851, dated October 3l, 1854.

.To aZZ whom it may concern;

Be it known that I, NATHANATHERTON, of the city of Philadelphia, and State of Pennsyl- Vania, have invented a new and useful improvement in the construction of steam-engines, for converting the reciprocating motion into a rotary motion and for operating the slide-valves of the engine; and I do hereby declare that the following is a full description of the same, reference being had to the annexed drawings, making part of this specification, in which- Figure lis a side view of a steam-engine and valves with my improved arrangement attached. Fig. 2 is an end view of the same. Fig. 3 is a view of the guides and ldrivingcylinder as seen from below. Fig. 4 is a side view of the detached part of Fig. 1, with a modified arrangement for working the slidevalves. Fig. 5 is an end view corresponding to Fig. 4.

To enable others skilled in the art to make and use my improvement, I will proceed to describe its construction and mode of operation.

A B C D, Fig. l, represent the cylinder of the steam-engine.

E F G H represent the steam-chest containing the ordinary slide-valves.

I K is the valve-rod. I L is the rock-shaft.

P P and P P are the guides on which the cross-head Q Q slides, Fig. 3.

d is afriction-roller placed upon the head of the pistonrod, which roller rolls in the grooves c c and c c as the piston moves backward and forward.

T U W V is the driving-cylinder mounted on the main shaft S S. It is a hollow metallic drum of cast-iron or brass, and has two helical grooves, c c' and c c, formed on its surface by the screw-like projections ct a a a and b b b b. These grooves start at the line c c and extend around right and left in the directions c c and c c to a line of the drum diametrically opposite the point C of the line C C, forming a double inclined plane or screw, the pitch and diameter of which are in proportion to the length of the stroke of the piston.

g g', Fig. 1, is a small inclined projection eX- tending radially outward from the drum and supported at its center on a small rod or shaft which passes diametrically across the drivingdrum. To the other extremity of the rod or shaft ff an inclined projection, h h', similar togg', is in like manner attached. The inclined projections g g and h h extend radially outward a short distance beyond the projection b b and b b. Two small friction-rollersz' and i', are placed upon the sliding rod L Yin such a position that as the driving-cylinder revolves the inclined projections g g and h 7L will alternately press against the rollerz' and the roller i', and thus at each half-revolution of the driving-cylinder the connectingrod L Y is alternately forced backward and forward. Through the medium of the rock-shaft I L and the valve-rod K .T the slide-valves are so acted upon that the steam shall be admitted behind the piston when the pistonhead is at that end of the driving-cylinder nearest the engine, and vice versa.

If it be desired to reverse the direction of rotation of 'the driving cylinder, then the projection g g is made to revolve upon the small shaft j' f', so as to occupy the position g g, and instead of pressing upon the roller t' it will press upon the roller i'. As the projection h his upon the same shaft, ff', a corresponding change in its direction of inclination will take place, and thus the slide-valves will be so acted on that the direction of rotation of the driving-cylinder will be reversed. In order conveniently to revolve the shaft f f and alter the relative position of g g and h it', these projections g g' and 7L It are geared in the following manner: A circular metallic disk, m n, turns upon a fixed center at o. A lever, p q, projects from this disk. An arm, st, connects the disk m n with the inclined projection g g'. Then the lever p q is in the position indicated in Fig. l, the projection g g is in the position shown in that figure. By moving the lever p g into the position p q the disk m n revolves ou O as a center and occupies the position m n', and the arm t s forces g g into the position g" g". As hh is attached to the other extremity of the shaft ff', the inclined projection h 7L at the same time time undergoes a corresponding change in the direction of its inclination.

Figs. 4 and 5 exhibit a modified arrangement of the inclined projections g g and 7th. In this modilication the inclined projections g g and h h form part of a thick metallic rim. (Shown in Figs. 4 and 5.) This metallic rim is supported by spokes 1 2, 3 4, and 5 6, radiating from a central hub, 7, which fits upon the main shaft S S and revolves with it. When it is desired to reverse the motion of the engine, the rim is to be turned half a turn in advance of the revolving drum, so as to bring the plane h hinto the position occupied by g g and the plane gg into the position occupied by h h', and thus change the motion of the slide-valves and reverse the action of the engine.

Having thus described my improvement, I do not claim adrvingcylinder having screwlike grooves, in combination with a pistonrod, for the purpose of converting reciprocating into continuous rotary motion; but

What I do claim is-` The connection of such a cylindenwith inclined projections, constructed and arranged substantially as herein described, for operating the valvegear by motion taken directly Vtnesses:

ALFRED C. GOWEN, CHARLES D. FREEMAN. 

